In recent years, electroluminescence devices that uses organic thin films (organic electroluminescence devices) have been developed. As formation methods of organic thin films (organic layers) of organic electroluminescence devices include vacuum evaporation method and wet coating method.
Vacuum evaporation method has advantages of improved charge injection from the anode and/or cathode and easy containment of excitons into the emitting layer, since it is easy to form a laminated structure by the method.
On the other hand, wet coating method has advantages such as no vacuum process, ease in forming large-area devices, and ease in mixing two or more kinds of materials having different functions in one layer (coating liquid).
However, it is difficult to form a laminated structure by wet coating method, and therefore, devices produced by the method are inferior to those produced by vacuum evaporation method in driving stability and thus most of them have not yet been developed to a practical level presently.
Particularly, it has been difficult to form a laminated structure of three or more organic layers by wet coating method, even though a laminated structure of two organic layers is possible by methods such as utilizing an organic solvent and an aqueous solvent.
In order to solve such problems with respect to lamination of organic layers, Patent Document 1, for example, discloses a process in which an organic layer of an organic electroluminescence device is formed through polymerization reaction of a film formed from a solution that contains a diamine compound having epoxy group.
In another instance, Non-Patent Document 1 discloses a process in which a hole-transport layer of an organic electroluminescence device is formed through polymerization reaction of a film formed from a solution containing a diamine compound having oxetane group.
By these methods, a solvent-resistant organic layer can be formed by wet coating method and thus three or more organic layers can be laminated.    [Patent Document 1] Japanese Patent Laid-Open Publication No. Hei 7-85973    [Non-Patent Document 1] Advanced Materials 2006, 18, 948-954.